PhD Student
Research Interests:
The importance of clean renewable energy has been underscored to secure new energy sources and protect environments. Especially, wind energy is appealing since it is economically competitive, technologically proven, infinitely renewable, and does not make any waste or carbon emission. Although they are considered to be more difficult to design than fixed offshore wind turbines, floating offshore wind turbines (FOWT) have many advantages compared to onshore or bottom fixed offshore wind turbines. In general, they are less restricted by governmental regulation and residents’ opposition, with higher-quality wind, and less sensitive to space/size/noise/visual/foundation restrictions. In addition, FOWT can be extended to the Multiple Unit Floating Offshore Wind Turbine (MUFOWT), which enables many wind-turbines to be installed on one floater and a larger blade to be equipped on higher point for capturing more wind energy. MUFOWT may also save installation and mooring-line cost, and it can be used for a multi-purpose energy station including other ocean renewable energy source. In this regard, if the technology is completely developed, floating offshore wind turbines are expected to be more popular to generate considerable amounts of clean renewable energy at competitive prices compared to other energy sources.
One of the challenging issues on the FOWT or MUFOWT is the coupled dynamics analysis among the mooring system, floating platform, and multi-wind turbines. Therefore, for reliable design, it is necessary to develop the integrated tool to accurately analyze the fully coupled dynamics including control. Some efforts are in progress toward this direction for several selected types of floating offshore wind turbines. We have made efforts to develop the fully coupled dynamic analysis tool for the single floating wind turbine: the combination of FAST and, and this tool was expanded in order to analyze MUFOWT by the second author’s research group.
The other issue is the health monitoring for floating offshore wind turbine. Despite various advantages of the floating offshore wind turbine (FOWT), it’s challenging for the floating wind turbine to be commercialize. Currently, the FOWTs installed in the real field were very few, and even FOWTs installed were just demonstration for the test. The one of the main reasons why the FOWTs were not commercialized is the uncertain operation and maintenance cost (OPEX). One way to decrease the uncertainness and reduce the OPEX is the structural health monitoring (SHM). By continuously monitoring the status of the tower or blade, required maintenance actions can be effectively scheduled, and it can make the inspection intervals increased as skipping the regular inspection when there are not any problems in the structure. In addition, catastrophic failures and secondary damage can be prevented as detecting an incipient damage.
Journal
Proceeding